1. Technical Field
The present invention relates generally to video processing, and more particularly relates to a system and method of effectively skipping decoding of overlaid areas of video without suffering a loss in quality.
2. Related Art
As new video-based technologies enter the marketplace, systems having advanced digital processing features, such as picture-in-picture, have become more desirable. Moreover, with the advent of technologies such as web-based and wireless-based video communications, the ability to efficiently process encoded video data has become particularly critical.
In systems that utilize encoded video with inter-picture coding, such as MPEG-2, MPEG-4, H.263, H.26L, and H.263++, the decoding of video data is recognized as an extremely computationally intensive process. When advanced processing features such as picture-in-picture are used, the computational requirements of the system are further exacerbated due to the need to decode and process multiple streams of video data, or process applications such as web browsing. Because typical decoding environments (e.g., a video phone) demand that decoding occur as close to real-time as possible with minimal delay, addressing the computational requirements of the decoder remains an ongoing challenge. In order to implement a video system with such advanced capabilities, the system must either include a processor that can provide the necessary amount of computational bandwidth, or include some means for reducing the processing overhead.
Unfortunately, providing a processor with large amounts of computational bandwidth significantly drives up the cost of the system. The other option, reducing the processing overhead, generally requires degradation to the video quality in order to implement the advanced features. While in certain circumstances some degradation to the video quality may be acceptable, it is always preferable to provide the highest quality video image possible. Accordingly, techniques are required that can provide advanced video features in a computationally efficient manner that will not cause degradation to the video image.